Add in np.nat guard
Add in np.nat guard

stuartarchibald/numba,cpcloud/numba,cpcloud/numba,gmarkall/numba,stuartarchibald/numba,gmarkall/numba,stuartarchibald/numba,IntelLabs/numba,stuartarchibald/numba,seibert/numba,numba/numba,jriehl/numba,numba/numba,numba/numba,stonebig/numba,numba/numba,jriehl/numba,stonebig/numba,sklam/numba,sklam/numba,sklam/numba,sklam/numba,gmarkall/numba,numba/numba,jriehl/numba,cpcloud/numba,gmarkall/numba,stuartarchibald/numba,seibert/numba,IntelLabs/numba,IntelLabs/numba,stonebig/numba,cpcloud/numba,seibert/numba,stonebig/numba,jriehl/numba,IntelLabs/numba,IntelLabs/numba,jriehl/numba,cpcloud/numba,sklam/numba,seibert/numba,seibert/numba,gmarkall/numba,stonebig/numba